land fact - managing scanned ewes - lambing
TRANSCRIPT
LAND FACT - AG PRODUCTION
Land fact Managing scanned ewes ndash Lambing (LF-AP-S-35)
Brent McLeod - Northern Tablelands Local Land Services Senior Land Services Oficer ndash Livestock (Sheep) Geof Duddy - Principal Consultant Sheep Solutions
A successful lambing outcome can be measured by ewe and lamb survival rates ewe milk production lamb growth rates live lambs and low lsquolamb and lossrsquo percentages at marking
Factors infuencingimpacting on ewe and lamb survival include
1 Ewe body condition prior to and during lambing
2 Environmental issues - temperaturerain wind protection from climatic extremes etc
3 Physical factors - available feed feed quality
4 Predation ndash may include both primary predationand losses incurred because of flock disturbancestress
5 Health and disease issues such as worms footabscessrot hypocalcaemia hypomagnesaemiapregnancy toxaemia
6 Misadventure (such as ewes becoming lsquocastrsquo)
Under most circumstances producers may have some control over the impacts of many of these factors Management and paddock design options available for minimising these impacts on ewe and lamb survival are discussed in this Land Fact
Ewe Body Condition Undernutrition of the ewe during pregnancy and lactation can impact heavily on
bull ewe live weight and body condition score
bull udder colostrum and milk development and yields
bull length and the relative ease of the birth process
bull lamb birth weight
bull lamb suckling driveviability and ultimately
bull ewe and lamb survival
Body condition score targets for single and multiple bearing ewes repercussions for under or over feeding the pregnant ewe and the fnancial benefts when meeting targets are discussed in Land Fact LF-AP-S-34 (Managing scanned ewes ndash Pre-lambing)
There are potentially many health and disease issues faced by the lambing ewe
wwwllsnswgovauregionsnorthern-tablelands
LAND FACT - AG PRODUCTION
Land fact Land Fact - Managing scanned ewes - Lambing - LF-AP-S-35
Environment Twins and triplets are generally lighter and smaller in size than their single born counterparts These lambs have comparatively larger surface area expend more energy so as to maintain body temperature and are at greater risk of death due to environmental extremes
Temperature rain and wind all contribute to what is known as the chill index The index is an estimate of an animalrsquos potential heat loss (kJm2hour) due to wind speed temperature and rainfall received over the previous 24 hours Mortality rates particularly in twin and triplet born lambs are known to increase when the wind chill index approaches 1000kJm2hour as shown in Figure 1 below
Figure 1 Relationship between the chill index (kJm2h) and the mortality of single and twin lambs (Source Evergraze)
The provision of shelter to reduce wind speed and therefore chill index (heat loss) has been shown to improve animal welfare lamb survival and ultimately profts
Paddock engineering through the strategic use of fencing shelter belts etc can help to reduce lamb deaths through modifying the ewersquos behaviour and minimising environmental extremes and impacts on her lambs
Sheep for example prefer to camp on the highest driest location in the paddock generally facing north-west (Marchant 1990) Fencing can prevent ewes from camping and lambing in these exposed locations with improvements in lamb marking percentages of between 9 to 20 recorded
Both natural (trees shrubs hedges etc) and artifcial (corrugated iron hessian etc) shelter belts have shown benefts in terms of reducing lamb deaths due to wind chill particularly among twin or triplet born lambs Shelter that reduces chill index by 50 to 100 kJm2hr has been shown to signifcantly increase twin born lamb survival rates (Lifetime Ewe)
Physical factors Available feed and feed quality are important factors within a lambing paddock
Recommended pasture targets for lambing single and multiple bearing ewes are 1500kg+ and 1800kg+ kilograms of dry matter (green food on offer)
Pasture quality in terms of energy protein and digestibility must also be considered
For example the energy requirements (MjMEhdday) for maintaining ewes in condition score 3 during late pregnancy will range from between 12 to 17 and from between 19 to 32 MjMEkgDMday depending on ewe frame weight and litter sizepregnancy status (Lifetime Wool)
Ewes approaching late pregnancy and during early lactation will also have an increased protein requirement Ewes should receive between 12 to 15 during late pregnancy and up to 17 protein when lactating
Highly digestible grass-based pastures containing upwards of 30 clovers or legumes are recommended If required supplements can be used to improve energy protein and whole ration digestibility When using supplements care needs to be exercised in order to prevent bull acidosis
o cereal grain versus pulses o introduction period o effective buffers o provision of effective fbre
bull mineral imbalances o additives
bull mismotheringdesertion o disturbances when feeding out o trail feeding vs self-feeders
wwwllsnswgovauregionsnorthern-tablelands
LAND FACT - AG PRODUCTION
Land fact Land Fact - Managing scanned ewes - Lambing - LF-AP-S-35
Predation Summary Dogs foxes pigs eagles crows etc are frequently responsible for lamb loss Degree and severity of lamb loss can vary between years and regions with losses able to be characterised as
1 Primary predation - where viable lambs are attackedtaken
2 Secondary predation - where lambs are likely to die andor have died prior to predation due principally to mismothering exposure or desertion by the ewe
3 lsquoDisturbancersquo related deaths ndash where lamb losses are caused by disruption or stress by predators This may be as simple as breaking of the ewelamb bond after birth due to the ewe being disturbed by the presence or actions of predators
4 Injuryinfection ndash crows pecking at the eyes tongue and anal areas of newborn lambs
Armstrong (2016) and Refshauge et al (2016) both reported primary predation to be responsible for ~7 of lamb deaths Others have reported as high as 30 to 40 While incidence (and cause) will vary between years and regions all producers should implement preventative measures prior to lambing to minimise the risk of losses through predators
Health and disease There are potentially many health and disease issues faced by the lambing ewe Common issues include pregnancy toxaemia prolapse dystocia clostridial diseases hypocalcaemia hypomagnesaemia and worms
Many of these are able to be prevented andor controlled through sound nutritional management prior to and during lambing
Armstrong (2016) reports that almost three-quarters of all lamb losses identifed were due to not meeting ewe needs (48 of deaths due to starvation andor mismothering) or over feeding (principally the single bearing ewe) with 25 of deaths due to dystocia (diffcult births)
Misadventure Misadventure or mishaps are unfortunately another cause of ewelamb death during lambing An example of misadventure would be ewe deaths caused by becoming lsquocastrsquo within hollows along drainage lines among timber etc
While misadventure is diffcult to predict andor prevent producers are urged to identify lsquosaferrsquo lambing paddocks or look to rectifyremove potential causes of misadventure
There are many factors infuencingimpacting on ewe and lamb survival rates during lambing Many of these are within the control of producers
It is critical that producers meet the pregnantlambing ewesrsquo feed needs Providing suitable pasture andor supplements and a safe low risk environment for the ewe and her lamb(s) will help to maximise lamb survival
References ArmstrongG (2016) Factors influencing reproductive wastage in Victorian sheep flocks httpsruneune eduauweb bitstream195911275998openpublished ThesisArmstrongGarryMRSc2017pdf Marchant B (1990) Paddock Design Grassland Society of NSW httpgrasslandnswcomaunewswp-contentuploads201109 Marchant-1990pdf Potential reproductive rate and the impacts of ewe nutrition in late pregnancy Session 4 Lifetime Ewe Manual (High Rainfall Zone edition)
Refshauge G Brien FD Hinch GN and van de Ven DR (2016) Neonatal lamb mortality factors associated with the death of Australian lambs httpswwwpublishcsiroauanan15121
Shelter improves lamb survival Evergraze https wwwevergrazecom aulibrary-contenthamilton-key-message-shelter-improves-lamb-survival
Supplementary feeding and feed budgeting for sheep DPRD (Agriculture and Food) httpswwwagricwagovaufeeding-nutrition supplementary-feeding-and-feed-budgeting-sheep
More Land Facts For additional information on feeding and management of scanned ewes please refer to Land Facts bull Managing scanned ewes ndash The basics bull Managing scanned ewes ndash The benefits bull Managing scanned ewes ndash Placental development bull Managing scanned ewes ndash Pre-lambing bull Managing scanned ewes ndash Lambing mob structure
For further advice andor information about improving your sheep enterprise contact Brent McLeod Senior Land Services Officer ndash Sheep Mobile 0413 884 710 Email brentmcleodllsnswgovau
For a complete list of Northern Tablelands Local Land Services Land Facts please visit our website at wwwllsnswgovauregionsnorthern-tablelands
Contacts and more information
copy State of New South Wales through Local Land Services 2021 The information contained in this publication is based on knowledge and understanding at the time of writing May 2021
However because of advances in knowledge users are reminded of the need to ensure that the information upon which they rely is up to date and to check the currency of the information with
the appropriate offcer of Local Land Services or the userrsquos independent adviser For updates go to wwwllsnswgovau
LAND FACT - AG PRODUCTION
Land fact Land Fact - Managing scanned ewes - Lambing - LF-AP-S-35
Environment Twins and triplets are generally lighter and smaller in size than their single born counterparts These lambs have comparatively larger surface area expend more energy so as to maintain body temperature and are at greater risk of death due to environmental extremes
Temperature rain and wind all contribute to what is known as the chill index The index is an estimate of an animalrsquos potential heat loss (kJm2hour) due to wind speed temperature and rainfall received over the previous 24 hours Mortality rates particularly in twin and triplet born lambs are known to increase when the wind chill index approaches 1000kJm2hour as shown in Figure 1 below
Figure 1 Relationship between the chill index (kJm2h) and the mortality of single and twin lambs (Source Evergraze)
The provision of shelter to reduce wind speed and therefore chill index (heat loss) has been shown to improve animal welfare lamb survival and ultimately profts
Paddock engineering through the strategic use of fencing shelter belts etc can help to reduce lamb deaths through modifying the ewersquos behaviour and minimising environmental extremes and impacts on her lambs
Sheep for example prefer to camp on the highest driest location in the paddock generally facing north-west (Marchant 1990) Fencing can prevent ewes from camping and lambing in these exposed locations with improvements in lamb marking percentages of between 9 to 20 recorded
Both natural (trees shrubs hedges etc) and artifcial (corrugated iron hessian etc) shelter belts have shown benefts in terms of reducing lamb deaths due to wind chill particularly among twin or triplet born lambs Shelter that reduces chill index by 50 to 100 kJm2hr has been shown to signifcantly increase twin born lamb survival rates (Lifetime Ewe)
Physical factors Available feed and feed quality are important factors within a lambing paddock
Recommended pasture targets for lambing single and multiple bearing ewes are 1500kg+ and 1800kg+ kilograms of dry matter (green food on offer)
Pasture quality in terms of energy protein and digestibility must also be considered
For example the energy requirements (MjMEhdday) for maintaining ewes in condition score 3 during late pregnancy will range from between 12 to 17 and from between 19 to 32 MjMEkgDMday depending on ewe frame weight and litter sizepregnancy status (Lifetime Wool)
Ewes approaching late pregnancy and during early lactation will also have an increased protein requirement Ewes should receive between 12 to 15 during late pregnancy and up to 17 protein when lactating
Highly digestible grass-based pastures containing upwards of 30 clovers or legumes are recommended If required supplements can be used to improve energy protein and whole ration digestibility When using supplements care needs to be exercised in order to prevent bull acidosis
o cereal grain versus pulses o introduction period o effective buffers o provision of effective fbre
bull mineral imbalances o additives
bull mismotheringdesertion o disturbances when feeding out o trail feeding vs self-feeders
wwwllsnswgovauregionsnorthern-tablelands
LAND FACT - AG PRODUCTION
Land fact Land Fact - Managing scanned ewes - Lambing - LF-AP-S-35
Predation Summary Dogs foxes pigs eagles crows etc are frequently responsible for lamb loss Degree and severity of lamb loss can vary between years and regions with losses able to be characterised as
1 Primary predation - where viable lambs are attackedtaken
2 Secondary predation - where lambs are likely to die andor have died prior to predation due principally to mismothering exposure or desertion by the ewe
3 lsquoDisturbancersquo related deaths ndash where lamb losses are caused by disruption or stress by predators This may be as simple as breaking of the ewelamb bond after birth due to the ewe being disturbed by the presence or actions of predators
4 Injuryinfection ndash crows pecking at the eyes tongue and anal areas of newborn lambs
Armstrong (2016) and Refshauge et al (2016) both reported primary predation to be responsible for ~7 of lamb deaths Others have reported as high as 30 to 40 While incidence (and cause) will vary between years and regions all producers should implement preventative measures prior to lambing to minimise the risk of losses through predators
Health and disease There are potentially many health and disease issues faced by the lambing ewe Common issues include pregnancy toxaemia prolapse dystocia clostridial diseases hypocalcaemia hypomagnesaemia and worms
Many of these are able to be prevented andor controlled through sound nutritional management prior to and during lambing
Armstrong (2016) reports that almost three-quarters of all lamb losses identifed were due to not meeting ewe needs (48 of deaths due to starvation andor mismothering) or over feeding (principally the single bearing ewe) with 25 of deaths due to dystocia (diffcult births)
Misadventure Misadventure or mishaps are unfortunately another cause of ewelamb death during lambing An example of misadventure would be ewe deaths caused by becoming lsquocastrsquo within hollows along drainage lines among timber etc
While misadventure is diffcult to predict andor prevent producers are urged to identify lsquosaferrsquo lambing paddocks or look to rectifyremove potential causes of misadventure
There are many factors infuencingimpacting on ewe and lamb survival rates during lambing Many of these are within the control of producers
It is critical that producers meet the pregnantlambing ewesrsquo feed needs Providing suitable pasture andor supplements and a safe low risk environment for the ewe and her lamb(s) will help to maximise lamb survival
References ArmstrongG (2016) Factors influencing reproductive wastage in Victorian sheep flocks httpsruneune eduauweb bitstream195911275998openpublished ThesisArmstrongGarryMRSc2017pdf Marchant B (1990) Paddock Design Grassland Society of NSW httpgrasslandnswcomaunewswp-contentuploads201109 Marchant-1990pdf Potential reproductive rate and the impacts of ewe nutrition in late pregnancy Session 4 Lifetime Ewe Manual (High Rainfall Zone edition)
Refshauge G Brien FD Hinch GN and van de Ven DR (2016) Neonatal lamb mortality factors associated with the death of Australian lambs httpswwwpublishcsiroauanan15121
Shelter improves lamb survival Evergraze https wwwevergrazecom aulibrary-contenthamilton-key-message-shelter-improves-lamb-survival
Supplementary feeding and feed budgeting for sheep DPRD (Agriculture and Food) httpswwwagricwagovaufeeding-nutrition supplementary-feeding-and-feed-budgeting-sheep
More Land Facts For additional information on feeding and management of scanned ewes please refer to Land Facts bull Managing scanned ewes ndash The basics bull Managing scanned ewes ndash The benefits bull Managing scanned ewes ndash Placental development bull Managing scanned ewes ndash Pre-lambing bull Managing scanned ewes ndash Lambing mob structure
For further advice andor information about improving your sheep enterprise contact Brent McLeod Senior Land Services Officer ndash Sheep Mobile 0413 884 710 Email brentmcleodllsnswgovau
For a complete list of Northern Tablelands Local Land Services Land Facts please visit our website at wwwllsnswgovauregionsnorthern-tablelands
Contacts and more information
copy State of New South Wales through Local Land Services 2021 The information contained in this publication is based on knowledge and understanding at the time of writing May 2021
However because of advances in knowledge users are reminded of the need to ensure that the information upon which they rely is up to date and to check the currency of the information with
the appropriate offcer of Local Land Services or the userrsquos independent adviser For updates go to wwwllsnswgovau
LAND FACT - AG PRODUCTION
Land fact Land Fact - Managing scanned ewes - Lambing - LF-AP-S-35
Predation Summary Dogs foxes pigs eagles crows etc are frequently responsible for lamb loss Degree and severity of lamb loss can vary between years and regions with losses able to be characterised as
1 Primary predation - where viable lambs are attackedtaken
2 Secondary predation - where lambs are likely to die andor have died prior to predation due principally to mismothering exposure or desertion by the ewe
3 lsquoDisturbancersquo related deaths ndash where lamb losses are caused by disruption or stress by predators This may be as simple as breaking of the ewelamb bond after birth due to the ewe being disturbed by the presence or actions of predators
4 Injuryinfection ndash crows pecking at the eyes tongue and anal areas of newborn lambs
Armstrong (2016) and Refshauge et al (2016) both reported primary predation to be responsible for ~7 of lamb deaths Others have reported as high as 30 to 40 While incidence (and cause) will vary between years and regions all producers should implement preventative measures prior to lambing to minimise the risk of losses through predators
Health and disease There are potentially many health and disease issues faced by the lambing ewe Common issues include pregnancy toxaemia prolapse dystocia clostridial diseases hypocalcaemia hypomagnesaemia and worms
Many of these are able to be prevented andor controlled through sound nutritional management prior to and during lambing
Armstrong (2016) reports that almost three-quarters of all lamb losses identifed were due to not meeting ewe needs (48 of deaths due to starvation andor mismothering) or over feeding (principally the single bearing ewe) with 25 of deaths due to dystocia (diffcult births)
Misadventure Misadventure or mishaps are unfortunately another cause of ewelamb death during lambing An example of misadventure would be ewe deaths caused by becoming lsquocastrsquo within hollows along drainage lines among timber etc
While misadventure is diffcult to predict andor prevent producers are urged to identify lsquosaferrsquo lambing paddocks or look to rectifyremove potential causes of misadventure
There are many factors infuencingimpacting on ewe and lamb survival rates during lambing Many of these are within the control of producers
It is critical that producers meet the pregnantlambing ewesrsquo feed needs Providing suitable pasture andor supplements and a safe low risk environment for the ewe and her lamb(s) will help to maximise lamb survival
References ArmstrongG (2016) Factors influencing reproductive wastage in Victorian sheep flocks httpsruneune eduauweb bitstream195911275998openpublished ThesisArmstrongGarryMRSc2017pdf Marchant B (1990) Paddock Design Grassland Society of NSW httpgrasslandnswcomaunewswp-contentuploads201109 Marchant-1990pdf Potential reproductive rate and the impacts of ewe nutrition in late pregnancy Session 4 Lifetime Ewe Manual (High Rainfall Zone edition)
Refshauge G Brien FD Hinch GN and van de Ven DR (2016) Neonatal lamb mortality factors associated with the death of Australian lambs httpswwwpublishcsiroauanan15121
Shelter improves lamb survival Evergraze https wwwevergrazecom aulibrary-contenthamilton-key-message-shelter-improves-lamb-survival
Supplementary feeding and feed budgeting for sheep DPRD (Agriculture and Food) httpswwwagricwagovaufeeding-nutrition supplementary-feeding-and-feed-budgeting-sheep
More Land Facts For additional information on feeding and management of scanned ewes please refer to Land Facts bull Managing scanned ewes ndash The basics bull Managing scanned ewes ndash The benefits bull Managing scanned ewes ndash Placental development bull Managing scanned ewes ndash Pre-lambing bull Managing scanned ewes ndash Lambing mob structure
For further advice andor information about improving your sheep enterprise contact Brent McLeod Senior Land Services Officer ndash Sheep Mobile 0413 884 710 Email brentmcleodllsnswgovau
For a complete list of Northern Tablelands Local Land Services Land Facts please visit our website at wwwllsnswgovauregionsnorthern-tablelands
Contacts and more information
copy State of New South Wales through Local Land Services 2021 The information contained in this publication is based on knowledge and understanding at the time of writing May 2021
However because of advances in knowledge users are reminded of the need to ensure that the information upon which they rely is up to date and to check the currency of the information with
the appropriate offcer of Local Land Services or the userrsquos independent adviser For updates go to wwwllsnswgovau